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动态土壤侵蚀包括依赖于空间与时间的土壤剥离、细沟的形成、水流中过量泥沙的沉积、沉积泥沙中细沟的再生等物理过程。与泥沙从沉积区域再剥离相关联的细沟再生是细沟变窄加深过程中的一个重要的现象。该文介绍一种实验装置 ,用于测量类似于沉积土壤的疏松土壤材料细沟再生的力学参数。用一种沙壤土进行实验 ,测定了不同团聚体大小和坡度下细沟再生开始和停止所对应的临界水流量。计算出了与沟坡相关的临界剪切应力。这些结果有助于理解细沟的再生及其数量关系 ,以及临界剪切应力与坡度间的定量关系 ;对于发展由沉积土壤再生的细沟演化过程模型特别有用。
Dynamic soil erosion includes physical processes such as soil detachment that depends on space and time, formation of thin furrows, excessive deposition of sediment in water streams, and regeneration of fine grooves in sediment. Rill regeneration, associated with the detachment of sediment from the sedimentary area, is an important phenomenon in the narrowing and deepening of the gutter. This paper presents an experimental setup for measuring the mechanical parameters of rill regeneration of loose soil material similar to that of sedimentary soils. Experiments were carried out on a sandy loam soil to determine the critical water flow corresponding to the start and stop of the rill recirculation at different aggregate sizes and gradients. The critical shear stress associated with the gully is calculated. These results are helpful to understand the regeneration of rill and its quantitative relationship as well as the quantitative relationship between critical shear stress and slope. It is especially useful for developing the model of rill evolution which is regenerated from sedimentary soils.